Thursday’s science was a bit different. Two boats went out to do some final surveying and follow up in Port Clarence and Grantley Harbor. Because the area of Grantley harbor to be surveyed was in less than 4 meters of water, an Ambar jet boat was used with a single beam sonar mounted aft on the port side. The second boat that went out was one of the small launches for use as a dive boat for NOAA trained divers (https://www.omao.noaa.gov/learn/diving-program). The goal of the dive boat was to dive on a particular location in Port Clarence that was giving a strange image that must have been coming from a man-made structure. The sonar showed a grid pattern roughly 100m x 60m with lines 7-8m apart on the long axis and 5-6m apart on the short axis. The team felt strongly that they needed to understand what was there in order to determine if it was safe for anchoring. I’ll follow up more on this later…

I went out with the team on the Ambar. As is the case with all the small launches, the Ambar is brought down from the boat deck to the breezeway deck for loading before the actual release.

Ambar jet boat at the breezeway deck, loading supplies. You can see parts of the davit where it was previously cradled on the boat deck above.

All gear, materials, food (long days out there!!) and people embark prior to the final drop to the water and the actual launch. This takes a team of a dozen or so people working in coordination. Prior to the start of launch, a safety officer is required on deck to oversee the process. This might be the CO (Commanding Officer), XO (Executive Officer) or Operations Officer. Most of the other personnel involved are a part of the deck crew, including the coxswain (who drives the small launches). A davit operator handles the control of the boat via cable(s) all the way down. The bosun (boatswain) on the breezeway deck is directing commands to the operator using hand signals. Several hands are securing the craft with ropes against the side of the ship. All of these moves have to happen in perfect coordination for the safety of everyone and the protection of the Ambar and Fairweather. Personal protective equipment is worn by all parties throughout. This includes a flotation vest or jacket and a hard hat which you can see on those on the boat in the image to the left.

Five of the other six small launches on the Fairweather undergo a similar process. Each is housed in a davit cradle and each has one or more cables to control the craft during its descent toward the waterline. The davits all shift their cradling position while the cables lift to assist in the release of the craft. Once the craft is entirely free of the cradle, it is slowly lowered down the side of the vessel to the breezeway deck for loading as described above. One boat, though, has a really cool option. This is the FRB or Fast Rescue Boat. This craft can actually be launched by the driver, which is a requirement of any FRB.

Workboat on the fantail – note the three lines attached, two at the stern and one at the bow. These are handled expertly by the deck crew during launch to keep her true.

The final craft is a workboat which is housed on the fantail. It is not used for surveying, but will often be employed as passenger transport. It is also used for pick up and drop off of material that may be used on land, such as the HorCon station discussed in my previous post. This craft is not seated in a davit cradle and is instead launched through the use of a very large crane (see image below). The crane is attached to the launch at a center point connected with three lines.

Crane on the Fairweather boat deck centered between four small launch davits.

The craft is moved from the position on the fantail to either the port or starboard side level with the deck and lowered to the water before loading. For this reason, it is much more difficult to keep it completely horizontal and not hitting the deck and doing damage to the Fairweather.

So back to the Ambar and what we were actually doing in Grantley Harbor. Much of the harbor is quite shallow and when a team had been in there previously, they felt that there may be some irregularity to the otherwise uniform seafloor. They had been getting some interference and scattering on the side scan. They wanted to understand why and also to get a complete picture of the harbor seafloor. With the Ambar and the single beam sonar, there is little to no danger of doing damage in extreme shallows since the equipment is not on the underside of the boat and the Ambar itself can be beached as there are no propellers.

Single beam sonar in its mount on the stern of the Ambar. It is in the down position as it will be when launched tomorrow.

We took the boat into the shallows with the single beam sonar to take measurements along lines to as shallow as 2m. While surveying in the shallows, we found that there were sea grasses growing and according to the Operations Officer who was on board, that may have been the reason for the interference. Regardless, we continued to survey a regular pattern in order to have good data for future charts. During this time, I was given the opportunity to drive the Ambar… which showed me how much more difficult staying a straight line course is than the coxswains make it look.

Yep. The outlined line is my line. I am reasonably proud that I actually manage to make it from one side to another. But even that was with a WHOLE lot of coaching!!

Upon return to the Fairweather, the Ambar is reattached to the cable and brought back up to the breezeway deck. Ropes are again used in coordination to keep the boat steady as it is lifted, much the reverse of what was described above. At that point all materials are unloaded and all the people disembark. The Ambar is then hoisted back up into the davit cradle.

When I’m back in an area with lots of bandwidth, I’ll create a video post to show just how cool the launches of small boats really is…

Personal Log

Shipboard life on a NOAA vessel is quite different from life on land. First, because the ship is a twenty four hour operation, people are needed at all hours. Many of the positions on NOAA vessels run on a 4 hours on, 8 hours off cycle. Some positions have recently shifted to 4 on, 4 off, 4 on, 12 off to afford greater lengths of time for sleep. When you are on the lower decks, it is also easy to lose track of time – and of course when you’re in Alaska during summer, it’s still light out at 10 o’clock. There are auroras to potentially be seen in the wee hours and multibeam surveying that happens through the night. There are always people up and about doing things – so the ship is a busy place at all times.

And with this in mind, I have to admit I have not been doing a great job getting to sleep. But I do sleep well on the ship, the rocking is the best cure for insomnia I’ve ever experienced. And I have been eating incredibly well – and I mean INCREDIBLY well. Mealtimes are the same each day, so that’s a great help. I will talk more about the food and the kitchen in a future post. Fortunately, with all that good eating, there’s a gym on board, so I’ve been able to work some of it off. There’s also laundry on board and a lounge with lots of movies. I like it. And waking up to the ocean and a lovely sunrise each morning makes the tiredness not really matter much.

Light early in the eastern sky – the sun comes up all around you this far north. It’s truly lovely.

As a part of NOAA’s mission, we had the opportunity to go ashore at a small town at Port Clarence called Brevig Mission. It is a town of almost 400, most of whom are native to Alaska. While ashore, we were able to spend time talking with the people, purchasing some of their handcrafts and fish, and even visiting the school. The people live simple lives. They still hunt walrus, seal and whale and those foods are the staple of their diet through the frozen winter months. I found it fascinating that they use all of the parts of the animals – the items that I purchased were from seal and walrus.

On the left is an ornament made of seal fur and on the right is a pendant of walrus tusk.

The CO (Commanding Officer) also arranged for ship tours for people from the town. The folks were taken in the Ambar out to the Fairweather in small groups and shown around. It was fun speaking afterward with those who went – there was a lot of excitement! I am so grateful that I had the opportunity to go to the town. They have a crazy history (see the “Did you know?” section below.)

Mom with her two little girls down near the water on their ATV. This is the most common form of transport around Brevig Mission.

Did You Know?

This cross memorializes all of the residents of Brevig Mission who died in the 1918 flu. It now lays on the ground aside the mass grave. All of the names and ages of the victims are listed.

Brevig Mission was hit hard by the 1918 Spanish Flu, perhaps in percentage mortality, the hardest hit place in the world. Of the 80 residents of Brevig Mission, 72 succumbed to the flu and died in a 5 day period. It was absolutely devastating. One of the current residents shared with me that reaching 400 is encouraging to the town and everyone there believes that the town is continuing to grow.

This is the location of the mass grave from the 72 flu victims of the 1918 Spanish Flu. It is a sobering place.

In 1997, the lungs of a well-preserved victim in the mass grave were shipped to a molecular pathology lab in Washington, D.C. and the flu virus was reconstructed. The evidence showed that it was a bird flu (similar to the avian flus which plague our world today) but incredibly virulent as it passed from birds to humans. You can read more about the findings here. (http://www.gi.alaska.edu/alaska-science-forum/villager-s-remains-lead-1918-flu-breakthrough)

Over the past two days I have been introduced to tremendous amounts of the science of hydrography. In this blog post I will focus on the hardware used and the process of surveying. There are two types of sonar that are being employed. The first is side scan sonar and the second is multibeam sonar.

Side scan array sonar housed underneath one of the small launch vessels

Side scan is shorter range and performs better in shallower water. Side scan is used in conjunction with multibeam, however, as side scan does not give true depth values. The function of side scan is to show features evident on the ocean floor. For this reason, multibeam is run in conjunction with side scan in order to keep an accurate record of depths.

Multibeam sonar housed underneath another of the small launch vessels

Multibeam shows an exact depth. Due to the fact that it is an angular spreading band from the center of the underside of the launch, at shallow depths it will only show a very narrow strip of ocean floor.

Stop and imagine…a lit flashlight shining on a wall from only a few centimeters away. What happens to the image on the wall as you pull the flashlight back? The area of coverage of the image will become larger. The concept is similar for the multibeam in shallow versus deeper water.

Using multibeam in shallow water then would create a need for more passes closer together in order to cover an area. There are instances where using this technology even in shallow water would make sense, but for a full coverage survey, this would not be the case.

A CTD; it contains sensors for conductivity, temperature and density of the water column

The third piece of hardware used for the standard small boat launch hydrographic surveys is the CTD device. The CTD will measure conductivity of the water and also give both a temperature and density profile. The CTD is deployed multiple times during a survey as a tool to calibrate the data that is coming in via the sonar. Conductivity of the water gives an estimate of the total dissolved solids in the water. This information, along with the temperature and density will give an estimate of sound speed through the water column.

Stop and try this one for better understanding… knock on a door normally with your head roughly arm’s distance from the point where you are knocking. Now repeat the process of knocking, but with your ear pressed against the door approximately an arm’s length away from the knock. What is different? You should have noticed that a more precise (and typically louder) sound reached your ear. If you pay close attention, you will also notice that the sound reaches your ear more quickly. This is roughly analogous to how changes in the water column will affect sound speed.

The final piece of equipment used regularly for surveys is a HorCon (horizontal control) station. This is a land-based station that will help to define accurate position in the water. It allows for greater precision with global positioning data. The signals of satellites responsible for global position are affected daily by changing atmospheric conditions. Moreover, the precise positions of the satellites themselves are actually not well known in advance. This may result in a GPS location moving a few centimeters in one direction or another. While this is not going to heavily impact your ability to find a Starbucks in a strip mall, it can have a definite impact on the accuracy of charts for navigation. The HorCon station always remains in the same place on land, and can therefore be used to calibrate the measurements being read in the survey waters nearby and that information can be used along with corrected satellite positions since it is coming after the fact.

A nautical chart of the Port Clarence and Grantley Harbor area where we were surveying

Today we worked in Port Clarence, Alaska, both outside and inside of Grantley Harbor. Most of the depths being surveyed are in the 4-6 meter range. The particular area being surveyed had been previously surveyed in the 1950s by the US Coast and Geodetic Survey, likely using a single beam sonar system. The current survey is intended to note changes that have occurred since that prior survey and to accurately update all of the charts. The area of western Alaska is expected to increase in boat traffic over the coming years due to the opening of the Northwest Passage from the Pacific to the Atlantic via the Arctic. This route is significantly shorter for most shipping traffic than the route through the Panama Canal. Because of this expected increase in traffic, there is a need to identify areas for sheltering during heavy seas. Port Clarence is a natural inlet that offers some protection and holds potential for this purpose.

The process of surveying:
Two launches were deployed. I was on launch 2808, the second described here. The first was equipped with only multibeam sonar and the second had both multibeam and side scan. The plans for the two launches were different. The launch with only multibeam was working in an area of Grantley Harbor and covering an area that had previously been mapped to insure that the values were acceptably accurate. This focus existed primarily because of extra time available up in this area. The launch running the side scan was completing some unfinished work in Port Clarence and then did further work inside of Grantley Harbor. These areas, or “sheets” are described below. As a side note, small boat deployment is a fascinating and involved activity that I will discuss in a later blog.

Survey areas are broken up into sections known as “sheets” – each sheet has a manager. This person will be from either the NOAA Corps or a civilian member of the scientific survey team. The sheet manager will be responsible for setting up the plan for survey and doing all of the final checks after data has been gathered, cleaned and examined to determine if there are areas that should be rechecked or run again before it is completed and undergoes final processing.

A sheet manager will need to consider several questions prior to setting up the initial parameters for the survey. What is the depth being surveyed? What type of bottom is it? What type of coverage is needed? All of these factors will come into play when determining how the lines will be run – how long, how far apart, which sonar type, etc.
Once the plan is determined, it will be the job of the Operations Officer, LT Damian Manda, to parse out the duties and create a daily work plan to cover all of the areas. Each day, multiple launches will be sent out to gather data as described above. As the fieldwork finishes for the day, data will be transferred to a drive and then brought into the ship’s mapping room where night processers will begin the lengthy work of checking and cleaning the data so that it can all be ready for the final processing step prior to being sent to the client.

How good are those data?
There are several checks built into the data collection process. First, the survey team members on the launches are watching in real time. With three screens to work from, they are able to see what the sonars are seeing and can also set certain limits for the data that will alarm when something appears to be contrary to what’s expected. Night processors look for anomalies in the data like sudden inexplicable drops in depth in an otherwise flat surface or an extremely “noisy” area with little good data. Any area with a former survey will also be compared to the previous values with large differences signaling possible issues. Many trained eyes look at the data before it is accepted for charting and there will commonly be at least one return to an area to check and recheck prior to completion. One area in the current survey has continued to show odd results, so trained NOAA divers will dive the area to find out what is really going on.

Personal Log

So far this has been an amazing experience. I fully enjoy being among the crew of the Fairweather and living on the ship. It’s hard to say what my favorite part has been so far because I have honestly enjoyed all of it! Since we didn’t get underway until Monday, I had the opportunity on Sunday to roam around Nome with a couple of the other folks that are just here for two weeks, LT Joe Phillips and LCDR Ryan Toliver. I learned a lot more about both the NOAA Corps and the Public Health Service of which they are respectively a part. (These are two of the seven uniformed services – can you name the other five?) NOAA Corps officers are in command on all of the active NOAA commissioned ships and aircraft and you will learn a lot more about them in future posts. The PHS is an organization made up primarily of medical professionals. These folks serve in various medical and medical research positions around the nation. There are many who will work for the National Institutes of Health in research, or the Bureau of Prisons or commissioned vessels like Fairweather as practitioners. Unlike NOAA Corps, PHS is not on a billet cycle where every two to three years you will be moved to a new position in a different office or location. Similar to all of the other uniformed services, though, promotion through the ranks is both encouraged and desired.

As we walked all around Nome, this was one of the sights – the frame of a traditional fishing boat.

We also saw the marker for the end of the Iditarod race. I was able to see the historic beginning in Seward, Alaska back in 2010, so seeing the end in Nome was an unexpected treat. Nome also has Cold War-era missile early warning system arrays at the top of a mountain nearby. We had a chance to hike around them and see some of the interesting geologic features of the area. There’s so much more to talk about, but I think I’ll stop here and save shipboard life for my next post.

Did You Know…

… that the Iditarod has its historic beginnings with the Public Health Service? There were many children in interior and western Alaska dying of diphtheria in the early 1920s. When it reached epidemic proportions, the only doctor in Nome reached out to the PHS in the lower 48 to ask for help. Vials of serum were found and sent north to Seward, but then because of heavy ice and storming, dog sled teams were used to get the vials to the interior towns and to Nome. The original race along the Iditarod Trail was run as a memorial to the “Serum Run” and eventually evolved into the highly competitive race it is today.

Throughout my experience as a Teacher at Sea, it has been evident that the ocean and humans are inextricably interconnected. This was apparent from my very first evening in Homer when I came across an eagle poised next to its colossal nest assembled in the middle of three rusty pier pilings. An illustration of nature conforming to our presence on the water and what we deem to be acceptable for our environment.

Eagle with nest located in deep water port of Homer, AK

But, humankind must sometimes accept and conform to nature. The fishermen of Uganik Bay have built their fishing camps above the tidal line and strung out their nets where the fish traditionally run. Most of the men and women who live here have chosen to do so because this is where the fish are found. One such gentlemen is Toby Sullivan, a commercial fisherman, who in 1975 headed to Alaska from Connecticut to work on the Alaskan pipeline. Instead, he found himself fishing vs. working on the pipeline and to this day is still gill-netting salmon to make a living. Toby’s fishing camp, East Point, located on the south shore of the Uganik Bay, has had a net on the site for the past 80 years. And, unfortunately, we drifted into that site when a strong current took us by surprise while we were gathering water quality data over the side of the small sonar vessel. When this happened, Toby and his crew worked swiftly and diligently to secure their fishing gear while NOAA divers were summoned from the Rainier to safely help our vessel leave the area.

Toby Sullivan and crew work to install an additional line on their fishing set

A few evenings later, Mr. Sullivan and his crew came on board the Rainier as dinner guests and a rich discussion of hydrographic work and fishing gear followed. He explained in detail how he sets his fishing gear and offered the idea that a radio channel be utilized between NOAA’s small vessels that are working around fishing gear and the local fisherman, in order to facilitate better communication.

Toby Sullivan and XO (executive officer) Jay Lomincky

As I watched the exchange of ideas between Commanding Officer E.J. Van Den Ameele and Mr. Sullivan it appeared that both men recognized that both parties were interested in Uganik Bay because the ocean and humans are inextricably interconnected. The Rainier’s primary mission in Uganik Bay is to gather the necessary data to create accurate and detailed charts for navigational use by the local fisherman and other mariners. As a commercial fisherman, Mr. Sullivan’s primary interest is to keep his gear and crew safe while continuing to make a living from the harvest of local fish.

Toby Sullivan shares information about how he sets his fishing gear

Today the Rainier continues on with its mission of hydrographic work at sea using the multibeam sonar which is located on the hull of the Rainier. The swath that multibeam sonar on the Rainier covers is similar to the swath of the multibeam sonar on the smaller boats; the coverage area depends on the depth of the water. For example, at our current water depth of 226 meters, the swath of each pass that the multibeam sonar makes an image of is 915 meters wide. This evening, upon the completion of the work with the Rainier’s multibeam sonar we will depart the area and be underway for Kodiak, AK.

All Aboard!

Michael Bloom serves as as survey technician aboard the Rainier and kindly took some time with me to discuss his background and work aboard the Rainier.

I grew up in a military family, so I was actually born in England and have lived in Florida, Nebraska, Montana, Oregon and Washington. I went to college at Oregon State University located in Corvallis, OR and majored in earth systems with a focus on marine science.

How did you discover NOAA?:

Ever since I was a little kid instead of having posters of bands etc… I had posters of maps. NOAA Corps participated in career fairs at my university. I stopped at their booth my sophomore year and again my junior and senior year to learn more about their program. After learning more about NOAA I also focused on the marine aspect of earth science because I knew I wanted to work with them. Initially I didn’t know about the civilian side of NOAA, so I applied for the NOAA Corps two times and wasn’t accepted into the program, although I was an alternate candidate once. At some point, when speaking with an officer he told me to apply for a civilian position with NOAA. So, I applied and was accepted.

I’m happy to be on the civilian side because I get to work on the science side of the operations all of the time and I get to keep my beard!

I am survey tech and my primary duties include data acquisition and data processing. We can work to become the Hydrographer in Charge on the surveys after enough time working in the field and, if after the Field Operations Officer observes us, he feels confident that we are ready. Eventually I’d like to work for NOAA as a physical scientist, a job that would have me going out to sea several times a year but one that is primarily land based.

What do you love about your work with NOAA?:

I get paid to travel! I go to places that people pay thousands of dollars to visit and I actually get paid thousands of dollars to go there. I enjoy that I can see the real world application of the work that I do. Scientists are using our data and ultimately we could be saving lives by creating such accurate charts.

Personal Log

NOAA’s website for the Rainier states that the Rainier is one of the most productive and advanced hydrographic ships in the world. After spending two weeks working on board the Rainier, I couldn’t agree more. However, I don’t believe that it is only the cutting-edge technology that makes the Rainier one of the best hydrographic ships in the fleet. But rather a group of outstanding people at the helm of each of the different technical aspects of hydrography. Hydrographic surveying has many steps before the end product, a chart, is released. The people I met on board who are part of that process are teaching each other the subtle nuances of Rainier’s hydrographic mission in order to become even better at what they do. I am grateful for the time that the crew and Officers have graciously given me while I have been on board. I felt very welcome from the moment a NOAA Corps member picked me up at the airport throughout my stay on the Rainier as I continued to pepper everybody with questions. Thank you Rainier! I am confident that when I return to my classroom your efforts to help me better understand your work of hydrographic surveying will pay off. You have given me the gift of new knowledge that, when shared with my students has the potential to ignite in them the same excitement and passion for science that so many of you possess.

Geographical area of cruise: Southeast Alaska, including Chatham Strait and Behm Canal, with a Gulf of Alaska transit westward to Kodiak

Log date: June 19, 2013

Weather conditions: 10.93⁰C, less than 0.5 km visibility in thick fog, 95.42% relative humidity, 1013.38 mb of atmospheric pressure, light variable winds (speed of less than 3 knots with a heading between 24⁰ and 35⁰)

Explorer’s Log: Survey, sample, and tide parties

Scientists are explorers, wandering the wilderness of wonder and curiosity their with eyes and minds wide open to events, ideas, and explanations that no other humans may have previously experienced. And by definition, explorers — including scientists — also are builders, as they construct novel paths of adventure along their journeys, built always upon the strong foundations of their own reliable cognitions and skill sets.

Ensign Rosemary Abbitt making a level sighting measurement

Starting from their own observations of the world around them, prior knowledge, and context, scientists inject creativity and insight to develop hypotheses about how and why things happen. Testing those ideas involves developing a plan and then gathering relevant data (pieces of information) so that they can move down the path of whittling away explanations that aren’t empirically supported by the data and adding to the collective body of knowledge, so that they and others might better fathom the likely explanations that are behind the phenomena in question.

NOAA Ship Rainier lowers launch vessel RA-5 for a survey excursion.

Because progress along the scientific path of discovery and explanation ultimately depends on the data, those data must be both accurate and precise. Often these terms are confused in regular conversation, but each word has its own definition.

A view from the skiff of the shoreline where the benchmarks and tide gauge staff already are installed.

Accuracy is a description of the degree of closeness or proximity of measurements of a quantity to the actual value of that quantity. A soccer player who shoots on goal several times and has most of his shots reach the inside of the net is an accurate shooter. Likewise, a set of measurements of the density of a large volume of seawater is more accurate if the sample data all are near the actual density of that seawater; a measurement that is 0.4% higher than the actual density of the water is just as accurate as another measurement of the same water that is 0.4% below the actual density value.

Before making more detailed data collections, Hydrographic Assistant Survey Technician (HAST) Curran first conducts a visual inspection of the previously-installed tide staff upon arriving at the shore.

Precision (also called reproducibility or repeatability), on the other hand, is the degree to which repeated measurements under unchanged conditions show the same results. If every shot attempted by the soccer player strikes the left goalpost four feet above the ground, those shots aren’t necessarily accurate – assuming that the player wants to score goals – but they are very precise. So, similarly, a set of measurements of seawater density that repeatedly is 5.3% above the actual density of the water is precise (though not particularly accurate).

HAST Curran collects data near the tide staff during the closing level run in Behm Canal.

The NOAA teams that conduct hydrographic surveys, collect seafloor samples, and gather data about tide conditions must be both accurate and precise because the culmination of their work collecting data in the field is the production of nautical charts and tide reports that will be used around the world for commerce, recreation, travel, fisheries management, environmental conservation, and countless other purposes.

Crew of the survey/sample team in the cabin of the launch vessel (and the Coxswain piloting the boat)

Hydrographic surveys of some sort have been conducted for centuries. Ancient Egyptian hieroglyphs show men aboard boats using ropes or poles to fathom the depths of the water. In 1807, President Thomas Jefferson signed a mandate establishing the Survey of the Coast. Since that time, government-based agencies (now NOAA’s Office of Coast Survey) have employed various systems of surveying depths, dangers, and seabed descriptions along the 95,000 miles of navigable U.S. coastlines, which regularly change due to attrition, deposition, glaciation, tectonic shifts, and other outside forces.

For most of that history, data were collected through a systematic dropping of weighted lines (called “lead lines”) from boats moving back and forth across navigable channels at points along an imaginary grid, with calibration from at least two shore points to assure location of the boat. Beyond the geometry, algebra, and other mathematics of measurement and triangulation, the work was painstakingly slow, as ropes had to be lowered, hauled, and measured at every point, and the men ashore often traveled alongside the boat by foot across difficult and dangerous terrain. However, the charts made by those early surveys were rather accurate for most purposes.

Starboard of launch vessel RA-4

The biggest problem with the early charts, though, was that no measurements were made between the grid points, and the seafloor is not always a smooth surface. Uncharted rocks, reefs, or rises on the seabed could be disastrous if ships passed above them.

HSST Barry Jackson pulls a line hand over hand to retrieve a scooped sea floor sample from a depth of more than 45 meters in Behm Canal.

… and then analyzes what the scoop captured: mud and gravel in this case.

Starting in the 1990s, single-beam sonar became the primary mechanism for NOAA’s surveys. Still looking straight down, single-beam sonar on large ships and on their small “launch vessels” (for areas that couldn’t be accessed safely by larger craft) provided a much more complete mapping of the seafloor than the ropes used previously. Sonar systems constantly (many times per second) ping while traveling back and forth across and along a channel, using the speed and angle of reflection of the emitted sound waves to locate and measure the depth of bottom features.

Data about sea floor samples first are recorded by hand on a chart aboard the launch vessel before being uploaded to NOAA computers later.

Sound waves travel at different speeds through different materials, based on the temperature, density, and elasticity of each medium. Therefore, NOAA also deploys CTD devices through columns of surveyed waterways to measure electrical conductivity (which indicates salinity because of ionization of salts dissolved in the water, thus affecting solution density), temperature (which usually is colder at greater depths, but not necessarily, especially considering runoff from glaciers, etc.), and depth (which generally has a positive-variation relationship with water pressure, meaning more pressure – and thus, greater density – as depth below the surface increases).

This CTD device measures conductivity, temperature, and depth in the water. All three affect the speed of the sound waves in water, and the speed of sound is a necessary bit of data when using sonar (which tracks reflected pings of sound) to determine the distance to the sea floor.

The most modern technology employed by NOAA in its hydrographic surveys uses multi-beam sonar to give even more complete coverage of the seafloor by sending sound waves straight downward and fanned outward in both directions as the boat travels slowly forward. Even though sonar beams sent at angles don’t reflect as much or as directly as those sent straight downward, uneven surfaces on the seabed do reflect some wave energy, thus reducing the occurrence of “holidays” (small areas not well-defined on charts, perhaps named after unpainted bits of canvas in portraits because the painter seemed to have “taken a holiday” from painting there).

Aboard the small launch vessel, everyone works. This is Teacher At Sea Rob Ulmer hauling in a sea floor sample in Behm Canal.

But that’s not all. To help sailors make decisions about navigation and anchoring – and often giving fishermen and marine biologists useful information about ecology under the waterline – NOAA also performs systematic samples of the types of materials on the sea floor at representative points in the waterways where it conducts surveys. Dropping heavy metallic scoop devices on lines* dozens of meters long through waters at various locations and then hauling them back aboard by winch or hand-over-hand to inspect the mud, sand, silt, gravel, rocks, shells, plants, or animals can be physically demanding labor but is necessary for the gathering of empirical data.

* A note about terminology from XO Holly Jablonski: Aboard the ship, lines have a job. Think of a “rope” as an unemployed line.

Additionally, Earth’s moon and sun (along with several underground factors) affect the horizontal and vertical movement of water on Earth’s surface, especially due to their gravitational pulls as Earth spins on its axis and orbits the sun and as the moon orbits Earth. Therefore, information about tides is extremely important to understanding the geography of nautical navigation, as the points below the waterline are identified on charts relative to the mean low water mark (so sailors know the least amount of clearance they might have beneath their vessels), and points above the waterline are identified relative to the mean high water mark (including notation of whether those object sometimes are fully submerged).

Can you see the evidence of tidal changes along the shoreline of Behm Canal? Color differences form strata along the rocks, and lowest leaves of the trees give further evidence of the highest reach of the water.

Ensign Damian Manda manually levels the sighting rod upon the “turtle” using a carpenter’s bubble-leveling device.

To gather accurate and precise data about tidal influences on local waters, NOAA sends tides-leveling shore parties and dive teams into difficult conditions – commonly climbing up, down, and across rock faces, traversing dense vegetation, and encountering local wildlife (including grizzly bears here in Alaska!) – to drill benchmarks into near-shore foundation rocks, install (and later remove) tidal gauges that measure changing water heights and pressures, and use sophisticated mathematics and mechanics to verify the levels of those devices.

Ensign Rosemary Abbitt and HST Brandy Geiger ponder the placement of equipment before the next level measurement.

Needless to say, this description is significantly less detailed than the impressively intricate work performed at every level by NOAA’s hydrographic scientists, and in the end, all of the collected data described in the paragraphs above – and more, like the velocity of the sonar-deploying vessel – must be analyzed, discussed, and interpreted by teams of scientists with broad and deep skills before the final nautical charts are published for use by the public.

A leveling rod is balanced on the highest point of a “turtle,” positioned carefully to be seen from multiple points.

As you choose where and how to proceed in your own journeys, remember that you can be more confident about your decision-making by using information that is both accurate and precise. And keep exploring, my friends.

This is the view from the benchmark atop a rocky outcropping (under an 80-foot evergreen) along Behm Canal while righting a measurement rod with the tide gauge leveling party.

Did You Know?

NOAA Ship Rainier in Behm Canal with launch vessels underway

Every ship in the NOAA fleet also is a voluntary mobile weather station, and so are many other seagoing vessels around the world. For many years ships have been required to report their locations and identities on a regular basis to agencies like the U.S. Coast Guard and local or regional harbormasters. Those periodic reports were (and still are) vital for local traffic control on the waters and for helping to provide quick response to emergency situations on vessels at sea.

The view aft through Behm Canal from the launch vessel

Eventually, someone insightful realized that having the ships also provide weather reports from their positions along with those identity-and-location reports would make a much richer and broader network of timely data for the National Weather Service, which is another branch of the National Oceanic and Atmospheric Administration. As NWS adds the weather data from those many boats to the data gathered at land-based NWS stations and from voluntary land-based reporters of conditions, their models and forecasts become stronger.

(For more info about being a volunteer weather observer or volunteering with NOAA in some other capacity related to oceans, fisheries, or research, please visit www.volunteer.noaa.gov.)

Especially because weather conditions are the results of interactions among local phenomena, regional climate, and the global systems, building more accurate and precise forecast models depends on information from everywhere, but the result is that everyone benefits from the better forecasts, too.

Southeast Alaska is area with frequent tectonic activity, including uplift and earthquakes. Here a scar among the trees on the mountainside shows evidence of tectonic shifts, which also creates a ready path for meltwater to move downhill from the snowy mountaintop to the seawater below, taking trees and soil with it.

Monday started with my alarm beckoning my eyes to open at 4:15am. I found my right pointer finger hitting snooze not once, but twice, only to finally move myself from the medium of a dreamlike state to a stand-up position at 4:36. I made it to the galley for breakfast and a safety brief for the 3102 launch.

Safety Brief. Mapping locations and surveys to be accomplished along Fisher Island.

Today I will be joining COXSWAIN Tom Bascom and HIC Matt Vanhoy to perform near-shore surveying on sections that have both holidays and missed information. Holidays do not mean we will be scanning for Santa’s missing sleigh, or find Columbus’s ship Santa Maria run aground, but rather areas that have been previously surveyed and unfortunately recorded absolutely no information. Holidays occur sometimes due to rough seas, oxygen, as well as possible rocky ocean floors.

After Tom, Matt, and I were lowered in the 3102 by the davit and help of the TJ crew, we went to Fisher Island and began the slow mowing movements of surveying. The ride to Fisher Island was incredibly bumpy and the entire deck was wet from the swells pushing up at the bow. Currently there are winds upwards of 16 knots and a chill in the air. Vanhoy is below deck in the surveying room and Bascom is manning the boat. Me, well, I am observing for now and loving the chaotic changing seas. After about 2 hours on deck with Tom I went below to the survey room… that lasted about 20 minutes. I became really sea sick and returned to deck with Tom. Matt told me that he often gets sea sick while surveying on the launches and will come up to the stern, puke, and continue on through the day (wow). When you are on a launch the motions of the ocean are magnified and you can feel the movements much more so than on the ship.

Polygons and

While we were passing by the massive houses located on Fisher Island, Tom commented that unless there is love inside the homes, they are like the numerous clam shells we find already emptied and eaten by fish and gulls. He said that peace and happiness is not a large house, but the land that surrounds the home. Tom has been on the open waters for the past 30 years and has found solace in simplicity. He is a determined individual who presses on and is concerned with following protocol and ensuring the safety of those around him.

After lunch we finished our survey sections and still had 3 hours before needing to return so went around the area and collected bottom samples. Bottom samples (BS) is probably the most fun thing I have been able to help with on the ship. We used a device called the Van Veen Grab system and lowered it into the water. When we thought the Sampler was in contact with the ocean floor we pulled a few times up and down on the line and then hoisted the grabber to the deck.

The bottom samples are taken for the fisheries division as well as for ships that are interested in areas that they will be able to anchor in. For the most part we pulled samples of course sand and broken clam shells (I hope this is no reflection of Fisher Island). The further away from the shore line we went the more courser the sand became as well the more rocks we sampled. Most of the rocks were metamorphic and consisted of marble and a little quartzite. This surprised me given the location. I though most of the rocks would be sedimentary based on the surrounding topography and surface features.

I appreciate Tom and Matt taking the time to review and connect me into each process. Tom taught me how to drive the launch… that was really FUN. With all of the monitors it was hard to discern between reality and a glamorous video game. Radar showed me where I was going, and a survey map outlined the areas I was trying to move to in order to take the next bottom sample. Watching everything at once is not easy to do because you also have to pay attention to the waters. The shoals (shallow waters) often have “pots” which are lobster traps placed everywhere. The pots have a cage on the bottom of the ocean floor and a huge buoy at the surface so you can locate them and steer clear of them.

Upon returning to the ship, I watched yet another amazing sunset and Matt take the survey data from the ship and upload it on the ship’s network while Tom and ENS Norman hosed down the salt from the deck and prepped the 3102 for a new day.

ENS Norman Hosing down 3101 after surveying Fisher Island for the day.

NOAA Teacher at Sea: Sue ZupkoNOAA Ship: PiscesMission: Study deep water coral, Lophelia Pertusa, in the Gulf StreamGeographical Area of Cruise: SE United States in Gulf Stream from off Mayport, FL to south of St. Lucie Inlet, FLDate: June 3, 2011Time: 15:33 EDT

Hello from the Pisces “flight” deck. I am sitting next to the pilots of the ROV. John Butler is currently flying the ROV at a depth of 243 meters. We are drifting with the ship as it makes its way to our survey site. The ROV has been in the water since around 9:00 this morning EDT and we have finished our lunch and are waiting to get to our drop site. Why is the ROV flying along at 243 meters when our survey site is at 300 meters? When the ROV first launched, the current was 3.5 knots above and below the surface. The ship’s crew on the bridge calculated how long it would take for us to arrive at the dive site given the currents. Once we started flying the ROV at depth, we found the counterweight acted as an anchor and the current slowed down above and below the surface. Accordingly, the ROV slowed down and it’s taking a lot longer to get to our dive site than originally calculated.

Jellyfish found on the way to the sea floor

What are we seeing on the video feed from the ROV? Lots of marine snow–detritus, zooplankton, and other small particles, plus a few interesting creatures– jellies, salps, several squid, arrow worms, and some hydrozoa. It really is surreal watching the video of our journey to the bottom of the sea.

Crew Members holding the ROV, helped by a winch

What are we expecting to find? Lophelia pertusa. Lophelia is a ture hard, or stony, coral from the phylum Cnidaria, class Anthozoa (meaning it is a polyp), class Anthozoa (starts as a larva swimming around and then becomes attached to something, or sessile). We want to find out how many there are, their health, their size, and what is living amongst them. Lophelia are white when they are alive, unlike shallow water corals that most people are familiar with which have colors from the algae which live with them. If the Lophelia is not white, it’s either sick or dead.

Science and Technology Log

On Wednesday, May 19, I was able to go out on a small boat launch. Four such boats were deployed from the Fairweather that morning. They all use 400 kilohertz multi‐beam sonar to map the bottom of the channels we are currently in, near Ketchikan, AK. This type of SONAR sends out 512 beams/ping of sound, and is most effective in shallow water. The area or swath that can be scanned at anytime is about 5 times the depth of the water. Therefore in shallow water the swath is much narrower and in deeper water the swath is much wider. Most of the work today on all of the launches was filling in small areas in the chart in which data was missing or not dense enough to complete the project. These areas are referred to as “holidays”, because they are areas where previous survey launches have been through the area and the data was not good enough. Some possible reasons for this could be that they are areas where acoustic noise was picked up by the multi‐beam SONAR, or where shadows were cast from the surface bedrock or boulders on the bottom of the channels. The area that we surveyed first is called Cascade Inlet.

Me on a small boat (launch) to survey the bottom of channels around

Me operating the multi‐beam sonar on the small boat launch

Not only did I get to use the computers on board to operate the SONAR and collect data, I was also able to deploy an instrument called a CTD that measures the conductivity, temperature and density of the water. This is very important because the speed of sound in water changes depending on the waters temperature density and conductivity. For example, the top layer of the water is typically a little warmer, less dense and less salty than deeper water due to influences from rain and inputs from rivers. When using SONAR you must know all of these factors in order to understand the speed at which sound waves will travel through the water. The sound waves will travel faster in cold deeper water, and the computer models take this into account before finalizing a chart. Ideally when using the CTD the sample must be taken at a depth that is greater than any spot you have surveyed so as to have a complete profile of these factors.

Me on a small boat (launch) pulling the CTD sampler back onto the boat.

In the afternoon we spent most of our time performing shoreline verification of small features around an area called Hog Rocks that have been previously identified. Here we used GPS (Global Positions Satellites), latitude and longitude, azimuth bearings, elevation and photos. As the name implies we were visiting small features to double check their exact location and exact heights.

On Thursday, May 20 I was scheduled to go out on a launch boat again but things did not go accordingly. There was a problem with the Davit, a mechanical crane that picks the 7 ton, 28 foot survey launch off the decks of the Fairweather and deploys them into the water. Since I was unable to go out and scan shallow water from the launch, I stayed on the Fairweather to scan and plot deeper water (approximately 400 meters) in and around Behm Canal. From the plot room of the ship I helped operate the computer, by starting and stopping the collection of data. In addition to filling in “holidays” we also mapped some cross lines. Cross lines are lines that run perpendicular to the main channel and are a means of verifying previous scans or quality control.

Example of shoreline features near Hog Rocks that we were verifying from the launch boats

Me, in the plot room on the Fairweather, collecting data.

Personal Log

I can’t say that the launch on May 19 was fun, but it was very cool and interesting. One thing no one told me was that after the morning rain was over that the sun would come out and it would reach almost 60 degrees, and that I should have brought sunscreen and a hat: warmer than it was in NY on this day. I now know for future launch days. I am usually going to be scheduled on a different launch team, doing slightly different tasks each day.

For now I just finished dinner, and yes it was very good again. In the meantime I am awaiting a debriefing of the day’s launches, and then hang out until bed. Before going to bed I went up to the highest deck on the Fairweather, called the flying bridge and watched one of the most beautiful sunsets unfold in front of my eyes.

What else, is on my mind…..Well SE Alaska is ridiculously beautiful, this coming from someone who has traveled a lot and used to work in the Grand Canyon. All over the place there is something new to see. I am still waiting for major whale sightings. Tuesday night before bed I caught a glimpse of some tails of a few porpoises (similar to dolphins), and Wednesday morning at the safety meeting on the stern of the boat (back) I sort of saw a whale surface for a moment. On Thursday, again at the safety meeting on the stern, a few of us saw a humpback whale at a distance breach the water a few times.

While at port, a picture showing the Davit, that picks up the launch boats to deploy them

Sun set on the Fairweather on May19

Bald eagle taking off on May19 from a shoreline feature we were verifying